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 * Copyright 2010 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. 
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 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
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 * Unless required by applicable law or agreed to in writing, software
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package org.jboss.logging;

import java.lang.reflect.Field;
import java.security.PrivilegedAction;
import java.util.Locale;

import static java.security.AccessController.doPrivileged;

A factory class to produce message bundle implementations.
Author:David M. Lloyd
/** * A factory class to produce message bundle implementations. * * @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a> */
public final class Messages { private Messages() { }
Get a message bundle of the given type. Equivalent to getBundle(type, Locale.getDefault()).
Params:
  • type – the bundle type class
Type parameters:
  • <T> – the bundle type
Returns:the bundle
/** * Get a message bundle of the given type. Equivalent to <code>{@link #getBundle(Class, java.util.Locale) getBundle}(type, Locale.getDefault())</code>. * * @param type the bundle type class * @param <T> the bundle type * @return the bundle */
public static <T> T getBundle(Class<T> type) { return getBundle(type, LoggingLocale.getLocale()); }
Get a message bundle of the given type.
Params:
  • type – the bundle type class
  • locale – the message locale to use
Type parameters:
  • <T> – the bundle type
Returns:the bundle
/** * Get a message bundle of the given type. * * @param type the bundle type class * @param locale the message locale to use * @param <T> the bundle type * @return the bundle */
public static <T> T getBundle(final Class<T> type, final Locale locale) { if (System.getSecurityManager() == null) { return doGetBundle(type, locale); } return doPrivileged(new PrivilegedAction<T>() { public T run() { return doGetBundle(type, locale); } }); } private static <T> T doGetBundle(final Class<T> type, final Locale locale) { String language = locale.getLanguage(); String country = locale.getCountry(); String variant = locale.getVariant(); Class<? extends T> bundleClass = null; if (variant != null && variant.length() > 0) try { bundleClass = Class.forName(join(type.getName(), "$bundle", language, country, variant), true, type.getClassLoader()).asSubclass(type); } catch (ClassNotFoundException e) { // ignore } if (bundleClass == null && country != null && country.length() > 0) try { bundleClass = Class.forName(join(type.getName(), "$bundle", language, country, null), true, type.getClassLoader()).asSubclass(type); } catch (ClassNotFoundException e) { // ignore } if (bundleClass == null && language != null && language.length() > 0) try { bundleClass = Class.forName(join(type.getName(), "$bundle", language, null, null), true, type.getClassLoader()).asSubclass(type); } catch (ClassNotFoundException e) { // ignore } if (bundleClass == null) try { bundleClass = Class.forName(join(type.getName(), "$bundle", null, null, null), true, type.getClassLoader()).asSubclass(type); } catch (ClassNotFoundException e) { throw new IllegalArgumentException("Invalid bundle " + type + " (implementation not found)"); } final Field field; try { field = bundleClass.getField("INSTANCE"); } catch (NoSuchFieldException e) { throw new IllegalArgumentException("Bundle implementation " + bundleClass + " has no instance field"); } try { return type.cast(field.get(null)); } catch (IllegalAccessException e) { throw new IllegalArgumentException("Bundle implementation " + bundleClass + " could not be instantiated", e); } } private static String join(String interfaceName, String a, String b, String c, String d) { final StringBuilder build = new StringBuilder(); build.append(interfaceName).append('_').append(a); if (b != null && b.length() > 0) { build.append('_'); build.append(b); } if (c != null && c.length() > 0) { build.append('_'); build.append(c); } if (d != null && d.length() > 0) { build.append('_'); build.append(d); } return build.toString(); } }